Chip had no EE, should PBP3 know that?

[aerostar]

24LC series is a possibility and does not need battery backup.

Serial EEPROM
• More than 1 Million Erase/Write Cycles - if that is enough
• Data Retention > 200 years

[Ioannis]

That million is valid for block write though...

[tumbleweed]

and that might work but I worry about the endurance as I would like to write many times

So, what's your definition of "many times", and when you say "I only use a few bytes" how many bytes is that?

[Dave]

If it was me, I would use an FM24W256 as it is a 256-Kbit ferroelectric random access memory (F-RAM)
logically organized as 32 K × 8. It has an unlimited write cycle and does NOT have the 5 Millisecond delay to write. I have used these in many projects that record data.
Dave Purola,
N8NTA
EN82fn